Autoimmunity: Why the Body Attacks Itself

The human body is made up of 37 trillion cells and billions of these die every single day. The body has special cells, called macrophages, which consume dying cells to prevent them from building up in your body.

Macrophages are also able to eat any cell that is infected by a bacterium or virus. This helps your body to remain as healthy as possible. Sometimes, the macrophages are given the wrong signals and they attack healthy cells. When this happens, your body develops an allergic reaction or inflammation that can lead to something called autoimmunity.